Method of exposing a wafer to a light, and reticle, reticle assembly and exposing apparatus for performing the same

ABSTRACT

A method of exposing a wafer to a light comprises transferring an image onto a plurality of shot areas by irradiating a projection light, each of the plurality of shot areas including at least one die area defined on the wafer on which a photoresist film is formed, and scanning the at least one die area adjacent to an edge portion of the wafer by irradiating a scanning light.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No. 11/023,231filed on Dec. 27, 2004, which claims priority under 35 U.S.C. §119 toKorean Patent Application No. 2003-97467, filed on Dec. 26, 2003, in theKorean Intellectual Property Office, the disclosure of which is hereinincorporated by reference in its entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to an exposing process for manufacturingsemiconductor devices; more particularly, a method of exposing a waferto a light, thereby transferring a pattern on a reticle onto the wafer,and an apparatus for performing the exposing method that includes areticle assembly.

2. Discussion of Related Art

Generally, semiconductor devices are manufactured by performing afabrication (FAB) process for forming an electric circuit on asemiconductor substrate, an electrical die sorting (EDS) process forinspecting electrical characteristics of the electric circuit, and apackaging process for separating the semiconductor substrate intoindividual semiconductor chips and sealing each of the semiconductorchips using, for example, an epoxy resin.

The FAB process includes a deposition process for forming a thin layeron the semiconductor substrate, a chemical mechanical polishing (CMP)process for polishing the thin layer, a photolithography process forforming a photoresist pattern on the thin layer, an etching process foretching the thin layer into an electrical pattern using the photoresistpattern as a mask, an ion implantation process for implanting ions intoa region of the semiconductor substrate, a cleaning process for cleaningimpurities from the semiconductor substrate, and an inspection processfor inspecting a surface of the semiconductor substrate to detectdefects in the thin layer or in the electrical pattern.

The photolithography process includes a coating process for coating aphotoresist composition layer on a silicon wafer, a baking process forhardening the photoresist composition layer into a photoresist film, anexposing process for transferring a pattern on the reticle (i.e., areticle pattern) onto the photoresist film, and a developing process forforming the photoresist pattern along the transferred reticle pattern.

An exposure apparatus for performing the exposing process includes alight source, an illumination unit for illuminating the reticle with alight from the light source, a reticle stage for supporting the reticle,a projection optical system for projecting a light passing through thereticle onto the wafer, and a wafer stage for supporting the wafer.Examples of the exposure apparatus are disclosed in U.S. Pat. No.6,331,885 (issued to Nishi) and U.S. Pat. No. 6,538,719 (issued toTakahashi et al.).

The reticle has a pattern corresponding to an image transferred onto aplurality of shot areas defined on the wafer. The reticle stage isdisposed over the projection optical system. The wafer stage is disposedunder the projection optical system.

An illumination light is generated from the light source. The reticle isirradiated by the illumination light having passed through theillumination unit during the exposing process. The reticle stage moveshorizontally for transforming the illumination light passing through thereticle into a projection light. The projection light contains imageinformation after passing through the reticle. The wafer stage moves inan opposite direction to the reticle stage so that the projection lighttransfers the image information onto the wafer.

A quantity and a size of the shot areas may be determined in accordancewith a characteristic and a usage of the semiconductor device. Theexposing process includes a first exposing process performed on the shotareas and a second exposing process performed on edge shot areas. Theedge shot areas are adjacent to edge portions of the wafer. The firstexposing process may be performed on all the shot areas of the wafer.Alternatively, the first exposing process may be performed on all theshot areas except for the edge shot areas of the wafer. The secondexposing process removes the photoresist film on die areas adjacent tothe edge portion of the wafer.

In a conventional single exposing process, the first exposing processmay use a conventional reticle having a single pattern as an exposuremask. The second exposing process in the conventional single exposingprocess may use a non-patterned reticle as the exposure mask. In aconventional multiple exposing process, a reticle having a multiplepattern areas may be used as the exposure mask.

In the conventional single exposing process, for performing the secondexposing process, the conventional reticle needs to be replaced with thenon-patterned reticle after completing the first exposing process. Inthe conventional multiple exposing process, the number of the shot areasmay increase because the pattern area of the reticle in the firstexposing process is smaller than that of the conventional reticle.

A need, therefore, exists to improve an exposure method and an exposureapparatus to reduce time loss in the conventional single exposingprocess and the conventional multiple exposing process.

SUMMARY OF THE INVENTION

In an exemplary embodiment of the present invention, a method ofexposing a wafer to a light comprises transferring an image onto aplurality of shot areas by irradiating a projection light, each of theplurality of shot areas including at least one die area defined on thewafer on which a photoresist film is formed, and scanning the at leastone die area adjacent to an edge portion of the wafer by irradiating ascanning light.

In another exemplary embodiment of the present invention, a method ofexposing a wafer to a light comprises irradiating a reticle having aprojection pattern corresponding to an image to be transferred onto thewafer with an illumination light, exposing a plurality of shot areas toa projection light that has passed through the reticle, each of theplurality of shot areas including at least one die area defined on thewafer on which a photoresist film is formed, moving the reticle and alight transmitting member such that the illumination light illuminatesthe light transmitting member, the light transmitting member beingdisposed adjacent to the projection pattern and having a projectionarea, and moving the wafer such that a scanning light that has passedthrough the light transmitting member scans die areas adjacent to anedge portion of the wafer.

In still another exemplary embodiment of the present invention, areticle for exposing a wafer to a light comprises a first regionincluding an image pattern irradiated by an illumination light, an imagecorresponding to the image pattern being transferred on a plurality ofshot areas, and each of the plurality of shot areas including at leastone die area defined on the wafer on which a photoresist film is formed,and a second region for exposing die areas adjacent to edge portions ofthe wafer to the illumination light, the second region being disposedadjacent to the first region.

In another exemplary embodiment of the present invention, a reticleassembly for exposing a wafer to a light comprises a reticle including aprojection pattern for transferring an image onto a plurality of shotareas using an illumination light, each of the plurality of shot areasincluding at least one die area defined on the wafer on which aphotoresist film is formed, a light transmitting member disposedadjacent to the reticle, the light transmitting member including a lighttransmitting area for exposing the at least one die area adjacent to anedge portion of the wafer to an illumination light, and a stage forsupporting the reticle and the light transmitting member.

In another exemplary embodiment of the present invention, an apparatusfor exposing a wafer comprises a light source for generating a light, areticle including a first region including an image pattern beingirradiated by the light, an image corresponding to the image patternbeing transferred on a plurality of shot areas including at least onedie area defined on the wafer on which a photoresist film is formed, anda second region for exposing die areas adjacent to edge portions of thewafer using the light, the second region being disposed adjacent to thefirst region, a reticle stage for supporting the reticle, anillumination unit for illuminating the reticle using the light, aprojection unit for projecting the light having passed through thereticle onto the wafer, and a wafer stage for supporting the wafer.

In another exemplary embodiment of the present invention, an apparatusfor exposing a wafer comprises a light source for generating a light, areticle assembly including a reticle having a pattern for transferringan image onto a plurality of shot areas using the light, each of theplurality of shot areas including at least one die area defined on thewafer on which a photoresist film is formed, a light transmitting memberincluding a light transmitting area for exposing die areas adjacent toan edge portion of the wafer using the light, the light transmittingmember being disposed adjacent to the reticle, and a reticle stage forsupporting the reticle and the light transmitting member, anillumination unit for illuminating the reticle and the lighttransmitting member using the light, a projection unit for projectingthe light having passed through the reticle and the light transmittingmember onto the wafer, and a wafer stage for supporting the wafer.

These and other exemplary embodiments, aspects, features and advantagesof the invention will become more apparent by describing in detailexemplary embodiments thereof with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart for showing a method of exposing a wafer to alight according to an exemplary embodiment of the present invention.

FIG. 2 is a structural view schematically illustrating an exposingapparatus for performing the exposing method shown in FIG. 1.

FIG. 3 is a plan view illustrating a wafer having a shot areasubstantially identical to a die area.

FIG. 4 is a plan view illustrating a wafer having a shot area includinga plurality of die areas.

FIG. 5 is a cross sectional view illustrating a reticle assemblyaccording to an exemplary embodiment of the present invention.

FIG. 6 is a perspective view illustrating the reticle and the lighttransmitting member shown in FIG. 5.

FIG. 7 is a perspective view illustrating the reticle stage shown inFIG. 5.

FIG. 8 is a cross sectional view illustrating a reticle assemblyaccording to another exemplary embodiment of the present invention.

FIG. 9 is a perspective view illustrating a light transmitting memberaccording to another exemplary embodiment of the present invention.

FIG. 10 is a perspective view illustrating another exemplary embodimentof the reticle.

FIG. 11 is a cross sectional view illustrating a reticle assemblyincluding the reticle shown in FIG. 10.

FIG. 12 is a perspective view illustrating a reticle stage shown in FIG.11.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Exemplary embodiments of the present invention now will be describedmore fully hereinafter with reference to the accompanying drawings.Embodiments of the invention may, however, be embodied in many differentforms and should not be construed as limited to the exemplaryembodiments set forth herein. Rather, exemplary embodiments are providedso that this disclosure will be through and complete, and will fullyconvey the scope of the invention to those skilled in the art.

FIG. 1 is a flow chart for showing a method of exposing a wafer to alight according to an exemplary embodiment of the present invention.FIG. 2 is a structural view schematically illustrating an exposingapparatus for performing the exposing method shown in FIG. 1.

Referring to FIGS. 1 and 2, a photoresist film (not shown) is coated ona silicon wafer W, and the photoresist film is formed into a photoresistpattern by an exposing and a development process. The photoresist filmis formed on the wafer W by a photoresist coating process and a softbaking process. The photoresist pattern may be used as an etching maskor an ion implantation mask.

A plurality of shot areas are defined on the wafer W. Each of theplurality of shot areas may include at least one die area. A size of thedie area may be determined in accordance with a kind of thesemiconductor device. A quantity and a size of each shot area may bedetermined in accordance with the size of the die area.

An exposing apparatus 10 according to an exemplary embodiment of thepresent invention includes a light source 12 for generating anillumination light, a reticle assembly 100, an illumination unit 14 forilluminating a reticle R using the illumination light, a projection unit18 for projecting the illumination light having passed through thereticle R on the wafer, and a wafer stage 20 for supporting the wafer W.Hereinafter, a light having passed through the reticle R is referred toas a projection light. The reticle assembly 100 includes the reticle R,a light transmitting member 102, and a reticle stage 104. The reticle Rhas a first image pattern (or a projection pattern) corresponding to aphotoresist pattern. The light transmitting member 102 has a lighttransmitting area that is shaped into a rectangular ribbon. The reticlestage 104 supports the reticle R and the light transmitting member 102.

A first image pattern of the reticle R is similar to an image to betransferred on the wafer W. The image corresponds to the photoresistpattern. That is, the illumination light passing the reticle R isconverted into the projection light containing image information by thereticle R.

The light transmitting member 102 is disposed adjacent to the reticle R.The light transmitting member 102 has a second image pattern forconverting the illumination light into a scanning light. The scanninglight may have a cross sectional surface that is shaped as a rectangularribbon. The second image pattern has a rectangular shape containing thelight transmitting area that is shaped into the rectangular ribbon. Thelight transmitting member 102 is used as a supplementary reticle forexposing the die area adjacent to an edge portion of the wafer W.

An eximer laser emitting eximer laser beams may be used as the lightsource 12. For example, a krypton fluoride (KrF) laser, an argonfluoride (ArF) laser and a fluorine (F2) laser may be used as the lightsource 12. The krypton fluoride (KrF) laser emits a krypton fluoridelaser beam having a wavelength of 248 nm. The argon fluoride (ArF) laseremits an argon fluoride laser beam having a wavelength of 193 nm. Thefluorine (F2) laser emits a fluorine laser beam having a wavelength of157 nm.

The light source 12 is connected with the illumination unit 14 through abeam matching unit. The illumination light generated from the lightsource 12 irradiates the reticle R or irradiates the light transmittingmember 102 through the illumination unit 14. The illumination lighthaving passed through the illumination unit 14 has a cross sectionalsurface that is shaped into the rectangular ribbon.

In an exemplary embodiment, the illumination unit 14 includes anillumination system housing 14A for sealing the inside thereof fromsurroundings, a variable beam attenuator 14B, a beam shaping opticalsystem 14C, a first fly-eye lens system 14D, a vibrating mirror 14E, acondenser lens 14F, a first mirror 14G, a second fly-eye lens system14H, an aperture stop plate 14J, a beam splitter 14K, a first relay lens14L, a reticle blind mechanism 14M, a second relay lens 14N, a secondmirror 14P, and a main condenser lens system 14Q.

The exposing apparatus 10 further includes a first driving unit 22 formoving the reticle stage 104 in a horizontal direction, and a seconddriving unit 24 for moving the wafer stage 20 in a horizontal direction.

When the exposing process is performed on the plurality of shot areas,the first driving unit 22 moves the reticle stage 104 in the horizontaldirection to convert the illumination light passing the reticle R intothe projection light containing image information. The second drivingunit 24 may simultaneously move the wafer stage 20 in an oppositedirection to the reticle stage 104. In another exemplary embodiment, thereticle stage 104 moves in a direction perpendicular to both a lightaxis of the illumination light and a longitudinal direction of a crosssectional surface of the illumination light. The wafer stage 20 may movein a direction perpendicular to both a light axis of the projectionlight and a longitudinal direction of a cross sectional surface of theprojection light. The wafer stage 20 may move in an opposite directionto the reticle stage 104.

When the exposing process is performed on the die areas adjacent to theedge portion of the wafer W, the illumination unit 14 irradiates thelight transmitting member 102 with the illumination light. The scanninglight having passed through the second image pattern of the lighttransmitting member 102 has a cross sectional surface that is shapedinto the rectangular ribbon. According to an exemplary embodiment, asize of the light transmitting area of the second image pattern issmaller than the cross sectional surface of the illumination light fromthe illumination unit 14. The second driving unit 24 moves the waferstage 20 in a direction perpendicular to both a light axis of thescanning light and a longitudinal direction of a cross sectional surfaceof the scanning light. As a result, the scanning light may irradiateseach of the die areas adjacent to the edge portion of the wafer W.

To control positions of the reticle R and the light transmitting member102, the first driving unit 22 may move the reticle stage 104 in ahorizontal direction perpendicular to the moving direction of thereticle stage 104, which corresponds to the longitudinal direction of across sectional surface of the illumination light. The first drivingunit may rotate with respect to with a central axis of the reticle R. Tocontrol position of the wafer, the second driving unit 24 may move thewafer stage 20 in a horizontal direction perpendicular to the movingdirection of the wafer stage 20, which corresponds to the longitudinaldirection of a cross sectional surface of the projection light or thescanning light. The wafer stage 20 may rotate with respect to with acentral axis of the wafer W.

FIG. 3 is a plan view illustrating a wafer having a shot areasubstantially identical to the die area. FIG. 4 is a plan viewillustrating a wafer having a shot area including a plurality of the dieareas.

Hereinafter, a method of exposing a wafer to a light according to anexemplary embodiment of the present invention is described withreference to the above figures. The reticle R and the light transmittingmember 102 are loaded on the reticle stage 104 (step S100). A wafer W isloaded on the wafer stage 20 (step S100). In an exemplary embodiment,the wafer W includes a plurality of shot areas S1 or S2 defined thereon.Each of the shot areas S1 or S2 has at least one die area D1 or D2. Theillumination light generated from the light source 12 irradiates thereticle R after passing through the illumination unit 14 (step S120).

A first exposing process may be performed on the plurality of the shotareas S1 or S2 using the projection light having passed through thereticle R (step S130). The reticle stage 104 and the wafer stage 20 maymove in an opposite direction to each other to transfer the first imagepattern on each shot area S1 or S2. After the first exposing process onthe plurality of the shot areas S1 or S2, the first driving unit 22 maymove the reticle stage 104 and the illumination light from theillumination unit 14 irradiates the light transmitting member 102 (stepS140).

A second exposing process may be performed on edge die areas D11 or D22adjacent to the edge portion W_(e) of the wafer W. The second exposingprocess uses the scanning light having passed through the lighttransmitting area of the light transmitting member (step S150). Duringthe second exposing process, the reticle stage 104 may be stopped andthe wafer stage 20 may move in a direction perpendicular to the lightaxis of the scanning light by the second driving unit 24. Thephotoresist film on the edge die areas D11 or D22 can be removed duringthe second exposure process.

As shown in FIG. 3, when each of shot areas is substantially identicalto each of die areas, the first exposing process is performed onnon-edge shot areas S12, and the second exposing process is performed onthe edge shot areas S11 or the die areas D11 adjacent to the edgeportion W_(e) of the wafer W.

As shown in FIG. 4, when each of the shot areas includes a plurality ofdie areas, the first exposing process may be performed on a whole shotarea S2 on the wafer W. The second exposing process is performed on thedie areas D22 adjacent to the edge portion W_(e) of the wafer W. In anexemplary embodiment, the edge portion W_(e) of the wafer W includes anedge portion P_(e) of the photoresist film.

Since the first exposing process is performed using the reticle R, andthe second exposing process is performed using the light transmittingmember adjacent to the reticle R, the whole shot area on the wafer canbe exposed without changing the reticle R. The size of the first patternarea of the reticle R is larger than the pattern area of theconventional reticle for the multiple exposure process. Thus, exposingtime can be reduced.

FIG. 5 is a cross sectional view illustrating a reticle assemblyaccording to an exemplary embodiment of the present invention. FIG. 6 isa perspective view illustrating the reticle and the light transmittingmember shown in FIG. 5. FIG. 7 is a perspective view illustrating thereticle stage shown in FIG. 5. FIG. 8 is a cross sectional viewillustrating the reticle assembly according to another exemplaryembodiment of the present invention.

Referring to FIGS. 5 through 8, the reticle assembly 100 includes areticle R, a light transmitting member 102, and a reticle stage 104. Thereticle R transfers an image onto a plurality of shot areas defined on awafer W on which a photoresist film is formed using an illuminationlight passing through the illumination unit 14. The light transmittingmember 102 exposes die areas adjacent to the edge portion of the wafer Wto the illumination light. The reticle stage 104 supports the reticle Rand the light transmitting member 102.

The reticle R includes a first image pattern 110 corresponding to aphotoresist pattern. Each of the shot areas defined on the wafer Wincludes at least one die area. The light transmitting member 102 isdisposed adjacent to the reticle R. The light transmitting member 102has a structure similar to the structure of the reticle R. The lighttransmitting member 102 includes a rectangular substrate 102 a, a secondimage pattern 112, and a light transmitting area 112 a. The rectangularsubstrate 102 a may be made from a light transmitting material. Thesecond image pattern 112 is disposed on the substrate 102 a and forms alight transmitting area 112 a of a rectangular ribbon shape.

In an exemplary embodiment, the reticle stage 104 is a rectangularplate. The reticle stage 104 includes a main opening 104 a through whichthe projection light passes after having passed through the reticle R.The reticle stage further includes a subsidiary opening 104 b throughwhich the scanning light passes after having passed through the lighttransmitting member 102. A plurality of first holders 120 for holdingthe reticle R using a vacuum is disposed around a peripheral portion ofthe main opening 104 a. A plurality of second holders 122 for holdingthe light transmitting member 102 using a vacuum is disposed around aperipheral portion of the subsidiary opening 104 b.

In another exemplary embodiment of the present invention, the lighttransmitting member 102 may be alternatively engaged with a peripheralportion of the subsidiary opening for covering the subsidiary opening asshown in FIG. 8. Referring to FIG. 8, the reticle R is held by thereticle holders 220. The reticle R covers the main opening 204 a of thereticle stage 204. The light transmitting member 202 is mounted on theperipheral portion of the subsidiary opening 204 b using a joint member230 such as, for example, a bolt. The light transmitting member 202 mayalso be adhered to the reticle stage 204 using adhesives.

FIG. 9 is a perspective view illustrating a light transmitting memberaccording to another exemplary embodiment of the present invention.Referring to FIG. 9, the light transmitting member 302 is a rectangularplate. The illumination light from the illumination unit 14 penetratesthe light transmitting member 302 through a slot 302 a. The lighttransmitting member 302 may be held by the second holders shown in FIG.7. Alternatively, the light transmitting member 302 may be engaged withthe reticle stage shown in FIG. 8 using the joint member shown in FIG. 8or adhesives.

The slot 302 a through which the illumination light passes may penetratethe reticle stage. In an exemplary embodiment, a cross sectional surfaceof the slot is smaller than that of the illumination light from theillumination unit 14.

FIG. 10 is a perspective view illustrating the reticle R for performingthe exposing method shown in FIG. 1 according to another exemplaryembodiment of the present invention. FIG. 11 is a cross sectional viewillustrating a reticle assembly including the reticle shown in FIG. 10.FIG. 12 is a perspective view illustrating a reticle stage shown in FIG.11.

Referring to FIGS. 10 through 12, the reticle assembly 400 includes areticle R1 for performing an exposing process on a wafer W and a reticlestage 404 for supporting the reticle R1. In an exemplary embodiment, thereticle R1 may be made from a light transmitting material and has arectangular plate. The reticle R1 includes a first region R11 on which afirst image pattern 410 is formed and a second region R12 on which asecond image pattern 412 is formed.

The first pattern 410 can be used as a projection pattern fortransferring an image onto a plurality of shot areas on the wafer Wusing an illumination light. Each shot area includes at least one diearea defined on the wafer W on which a photoresist film is formed. Thesecond pattern 412 can be used as a scan pattern for exposing an edgedie area adjacent to an edge portion of the wafer W to the illuminationlight.

The second image pattern 412 includes a light transmitting area 412 a ofa rectangular ribbon shape for scanning the edge die area adjacent tothe edge portion of the wafer W. The wafer W moves in a directionperpendicular to a longitudinal direction of the light transmitting area412 a. The scanning light irradiates the edge die area of the wafer W.

The reticle R1 is supported by the reticle stage 404. A plurality ofholders 420 for holding the reticle R1 using a vacuum is disposed on thereticle stage 404. The reticle stage 404 includes an opening portion 404a through which the projection light and the scanning light pass. Theprojection light can be formed through the first image pattern 410 andthe scanning light can be formed through the second image pattern 420.The reticle holders 420 are disposed around a peripheral portion of theopening portion 404 a.

According to another exemplary embodiment of the present invention, theexposing method may include a first exposing process and a secondexposing process. The first exposing process may be performed on aplurality of shot areas defined on the silicon wafer. The secondexposing process may be performed on a plurality of die areas adjacentto an edge portion of the wafer. The first exposing process may beperformed using a reticle having a first image pattern and the secondexposing process may be performed using a light transmitting memberadjacent to the reticle.

Accordingly, the exposing method can be continuously performed withoutchanging the reticle. Thus the exposing time can be reduced as comparedwith the conventional single exposing process. The exposing time canalso be reduced as compared with the conventional multiple exposingprocess using a reticle having a multiple pattern area. As a result, theexposing method and apparatus for performing the same according toexemplary embodiments of the present invention may improve thethroughput of the wafer in an exposure process.

Although exemplary embodiments of the present invention have beendescribed, it is understood that the present invention should not belimited to these exemplary embodiments but various changes andmodifications can be made by one skilled in the art within the spiritand scope of the present invention as hereinafter claimed.

1. A reticle for exposing a wafer to a light, comprising: a first regionincluding an image pattern irradiated by an illumination light, an imagecorresponding to the image pattern being transferred on a plurality ofshot areas, and each of the plurality of shot areas including at leastone die area defined on the wafer on which a photoresist film is formed;and a second region for exposing die areas adjacent to edge portions ofthe wafer to the illumination light, the second region being disposedadjacent to the first region.
 2. The reticle of claim 1, wherein thesecond region includes a second image pattern for forming a lighttransmitting area having a ribbon shape.
 3. A reticle assembly forexposing a wafer to a light, comprising: a reticle including aprojection pattern for transferring an image onto a plurality of shotareas using an illumination light, each of the plurality of shot areasincluding at least one die area defined on the wafer on which aphotoresist film is formed; a light transmitting member disposedadjacent to the reticle, the light transmitting member including a lighttransmitting area for exposing the at least one die area adjacent to anedge portion of the wafer to an illumination light; and a stage forsupporting the reticle and the light transmitting member.
 4. The reticleassembly of claim 3, wherein the light transmitting area has arectangular ribbon shape.
 5. The reticle assembly of claim 4, whereinthe light transmitting member includes a substrate comprising a lighttransmitting material and a pattern for forming the light transmittingarea on the substrate.
 6. The reticle assembly of claim 3, wherein thestage includes a main opening through which the illumination lightpasses after having passed through the reticle, and a subsidiary openingthrough which the illumination light passes after having passed throughthe light transmitting member.
 7. The reticle assembly of claim 6,further comprising first and second holders for respectively holding thereticle and the light transmitting member using a vacuum, the first andsecond holders being disposed at a peripheral portion of the mainopening and subsidiary opening, respectively.
 8. The reticle assembly ofclaim 6, further comprising a reticle holder for holding the reticleusing a vacuum, the reticle holder being disposed at a peripheralportion of the main opening.
 9. The reticle assembly of claim 8, whereinthe light transmitting member is engaged with a peripheral portion ofthe subsidiary opening for covering the subsidiary opening.
 10. Thereticle assembly of claim 9, wherein the light transmitting member has arectangular plate shape, and includes a slot therein through which theillumination light passes.
 11. The reticle assembly of claim 3, whereinthe reticle and the light transmitting member are in an integrallyformed structure.
 12. The reticle assembly of claim 11, wherein thestage includes an opening portion through which the illumination lightpasses after having passed through the reticle and the lighttransmitting member.
 13. The reticle assembly of claim 12, furthercomprising a holder for holding the reticle and the light transmittingmember using a vacuum, the holder being disposed at peripheral portionof the opening portion.
 14. An apparatus for exposing a wafer,comprising: a light source for generating a light; a reticle including afirst region including an image pattern being irradiated by the light,an image corresponding to the image pattern being transferred on aplurality of shot areas including at least one die area defined on thewafer on which a photoresist film is formed, and a second region forexposing die areas adjacent to edge portions of the wafer using thelight, the second region being disposed adjacent to the first region; areticle stage for supporting the reticle; an illumination unit forilluminating the reticle using the light; a projection unit forprojecting the light having passed through the reticle onto the wafer;and a wafer stage for supporting the wafer.
 15. The apparatus of claim14, wherein the second region includes a second image pattern forforming a light transmitting area having a ribbon shape.
 16. Theapparatus of claim 14, wherein the reticle stage includes an openingportion through which the illumination light passes after having passedthrough the first region and the second region.
 17. The apparatus ofclaim 16, further comprising a holder for holding the reticle using avacuum, the holder being disposed at a peripheral portion of the openingportion.
 18. An apparatus for exposing a wafer, comprising: a lightsource for generating a light; a reticle assembly including a reticlehaving a pattern for transferring an image onto a plurality of shotareas using the light, each of the plurality of shot areas including atleast one die area defined on the wafer on which a photoresist film isformed, a light transmitting member including a light transmitting areafor exposing die areas adjacent to an edge portion of the wafer usingthe light, the light transmitting member being disposed adjacent to thereticle, and a reticle stage for supporting the reticle and the lighttransmitting member; an illumination unit for illuminating the reticleand the light transmitting member using the light; a projection unit forprojecting the light having passed through the reticle and the lighttransmitting member onto the wafer; and a wafer stage for supporting thewafer.
 19. The apparatus of claim 18, wherein the light transmittingarea has a rectangular ribbon shape.
 20. The apparatus of claim 18,wherein the light transmitting member includes a substrate comprising alight transmitting material and a pattern for forming the lighttransmitting area on the substrate.
 21. The apparatus of claim 18,further comprising a driving unit for moving the wafer vertically withrespect to a light axis of the illumination light, so that the die areasare scanned by the light having passed through the light transmittingmember while die areas adjacent to the edge portion of the wafer areexposed.
 22. The apparatus of claim 18, wherein the reticle stageincludes a main opening through which the light passes after havingpassed through the reticle, and a subsidiary opening through which thelight passes after having passed through the light transmitting member.23. The apparatus of claim 22, further comprising first holder and thesecond holder for respectively holding the reticle and the lighttransmitting member using a vacuum, the first and second holders beingdisposed at a peripheral portion of the main opening and subsidiaryopening, respectively.
 24. The apparatus of claim 22, further comprisinga reticle holder for holding the reticle using a vacuum, the reticleholder being disposed at a peripheral portion of the main opening. 25.The apparatus of claim 24, wherein the light transmitting member isengaged with a peripheral portion of the subsidiary opening for coveringthe subsidiary opening.
 26. The apparatus of claim 25, wherein the lighttransmitting member has a rectangular plate shape, and includes a slottherein through which the light passes.
 27. The apparatus of claim 18,further comprising a first driving unit for driving the reticle in ahorizontal direction, and a second driving unit for driving the wafer inan opposite direction to the reticle while the image is transferred ontothe plurality of shot areas.